1. Field of the Invention
The present invention is related to a method for volume apportioning a quantity of paste substance to be distributed and a machine for distributing a paste substance in apportioned quantities using the apportioning method as per the invention.
The paste substance to be distributed in apportioned quantities can be an edible paste intended, for example, to fatten Palmipeds (geese or ducks).
2. Discussion of Background Information
In the field of force-feeding Palmipeds, automatic force feeders are known to be useful, and are basically comprised of a delivery and suction apportioning pump comprising a suction conduit in communication during suction, with a paste tank and a distribution conduit in which the quantity of paste is then delivered towards a force-feeding nipple mounted at the end of the distribution conduit and intubated into the maw of the Palmiped to be force fed.
The delivery and suction apportioning pump comprises a cylindrical apportioning chamber in which is slidably mounted a piston, driven by a motor member towards the front in the direction of delivery and towards the rear in the direction of suction.
The apportioning chamber comprises a terminal shutter wall that is pierced through by two orifices, the delivery conduit being connected to one of the orifices, and the suction conduit being connected to the other.
The suction and delivery conduits are each equipped with a blocking element such as a non-return valve. Such a force-feeding machine is especially disclosed in the patent FR-A-429,354.
This type of machine functions as follows: the blocking element associated to the distribution conduit being closed and the blocking element associated to the suction conduit being open, the piston is moved by the motor member in the direction of suction, and a quantity of paste is introduced axially into the cylindrical apportioning chamber. Then, after closure of the blocking element associated to the suction conduit and opening of the blocking element associated to the distribution conduit, the piston is moved in the direction of delivery and the quantity of paste previously introduced into the apportioning chamber of the pump is axially delivered from the latter towards the force-feeding nipple. The introduction of the paste into the apportioning chamber occurs progressively during the rearward movement of the piston. The apportioning of the amount to be distributed is done during suction and the volume of the quantity distributed is theoretically equal to the volume of the apportioning chamber when the piston is at the rear neutral position. This assumes that the apportioning chamber is filled in its entirety during suction.
It has been noted that with less liquid paste substances, the apportioning chamber only fills partially so that the portion distributed does not correspond to the desired portion. Furthermore, the degree to which the apportioning chamber is filled depends on the degree of liquidity of the edible paste to be distributed. Such edible paste being mainly constituted of water and flour, its degree of liquidity is a direct result of the degree of absorption of water by the flour, which varies over time.
This disadvantage is translated into a variation of the portion distributed and prior art machines do not ensure a precise and constant apportioning of the ration to be distributed.
The maw of Palmipeds (geese, ducks) is a pouch that should receive 300 ml of paste at the start of the force-feeding and 900 ml 12 to 15 days later.
The technique of force-feeding consists of developing this pouch a little more each day in order to increase its capacity in a uniform manner by playing with the elasticity of the maw and consequently, regularly increasing the quantity of food delivered to the animal.
It is important to oversee that force-feeding does not lead to distended maw tissues that are detrimental to the health of the animal. This distension of tissues can be the result of introducing too large a quantity of food into the maw and/or too fast a speed of introduction.
As such, it is important to have perfect control of the portion that is distributed, something which prior art machines do not allow, and to control the speed of introduction.
Prior art machines were envisioned to introduce substances at a slow speed. Although this arrangement enables the dangers of the distension of maw tissues to be partially removed, it remains nonetheless true that a slow speed does not enable the force-feeding to be done at a fast pace.